COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT

WATER QUALITY CONTROL COMMISSION

5 CCR 1002-36

REGULATION NO. 36
CLASSIFICATIONS AND NUMERIC STANDARDS
FOR
RIO GRANDE BASIN

APPENDIX 36-1

Stream Classifications and Water Quality Standards Tables

Effective 06/30/2017

REGULATION #36 STREAM CLASSIFICATIONS and WATER QUALITY STANDARDS

Rio Grande River Basin

4a. Mainstem of the Rio Grande from a point immediately above the confluence with Willow Creek to a point immediately above the confluence with the South Fork Rio Grande.
CORGRG04A
Designation
Reviewable
/ Classifications
Agriculture
Aq Life Cold 1
Recreation E
Water Supply
Qualifiers:
Other:
Temporary Modification(s):
Arsenic(chronic) = hybrid
Expiration Date of 12/31/2021
Cadmium(chronic) = current condition
Lead(chronic) = current condition
Zinc(chronic) = current condition
Ammonia(ac/ch) = current condition
Expiration Date of 12/31/2018
*Cadmium(acute) = See 36.6(4) for site-specific standards and assessment locations.
*Cadmium(chronic) = See 36.6(4) for site-specific standards and assessment locations.
*Lead(chronic) = See 36.6(4) for site-specific standards and assessment locations.
*Manganese(chronic) = See 36.6(4) for site-specific standards and assessment locations.
*Zinc(acute) = See 36.6(4) for site-specific standards and assessment locations.
*Zinc(chronic) = See 36.6(4) for site-specific standards and assessment locations.
/ Physical and Biological
DM
/ MWAT
Temperature °C
/ CS-II
/ CS-II
acute
/ chronic
D.O. (mg/L)
/ ---
/ 6.0
D.O. (spawning)
/ ---
/ 7.0
pH
/ 6.5 - 9.0
/ ---
chlorophyll a (mg/m2)
/ ---
/ ---
E. Coli (per 100 mL)
/ ---
/ 126
Inorganic (mg/L)
acute
/ chronic
Ammonia
/ TVS
/ TVS
Boron
/ ---
/
/ 0.75
Chloride
/ ---
/
/ 250
Chlorine
/ 0.019
/ 0.011
Cyanide
/ 0.005
/ ---
/
Nitrate
/ 10
/ ---
/
Nitrite
/ ---
/
/ 0.05
Phosphorus
/ ---
/
/ ---
/
Sulfate
/ ---
/
/ WS
Sulfide
/ ---
/
/ 0.002
/ Metals (ug/L)
acute
/ chronic
Aluminum
/ ---
/ ---
Arsenic
/ 340
/ 0.02(T)
Beryllium
/ ---
/ ---
Cadmium
/ varies*
/ varies*
Chromium III
/ 50(T)
/ TVS
Chromium VI
/ TVS
/ TVS
Copper
/ TVS
/ TVS
Iron
/ ---
/ WS
Iron
/ ---
/ 1000(T)
Lead
/ TVS
/ varies*
Manganese
/ TVS
/ varies*
Mercury
/ ---
/ 0.01(T)
Molybdenum
/ ---
/ 160(T)
Nickel
/ TVS
/ TVS
Selenium
/ TVS
/ TVS
Silver
/ TVS
/ TVS(tr)
Uranium
/ ---
/ ---
Zinc
/ varies*
/ varies*
7. Mainstem of West Willow Creek from the Park Regent Mine dump to the confluence with East Willow Creek. Mainstem of Willow Creek, including all tributaries from the confluence of East and West Willow Creeks, to the confluence with the Rio Grande.
CORGRG07
Designation
UP
/ Classifications
Agriculture
Aq Life Cold 2
Recreation E
Qualifiers:
Other:
Temporary Modification(s):
Cadmium(ac/ch) = varies*
Copper(ac/ch) = varies*
Lead(ac/ch) = varies*
Silver(acute) = varies*
Zinc(ac/ch) = varies*
Ammonia(ac/ch) = current condition
Expiration Date of 12/31/2018
*chlorophyll a (mg/m2)(chronic) = applies only above the facilities listed at 36.5(4).
*Phosphorus(chronic) = applies only above the facilities listed at 36.5(4).
*Cadmium(acute) = See 36.6(4) for temporary modifications, site-specific standards and assessment locations.
*Cadmium(chronic) = See 36.6(4) for temporary modifications, site-specific standards and assessment locations.
*Copper(acute) = See 36.6(4) for temporary modifications, site-specific standards and assessment locations.
*Copper(chronic) = See 36.6(4) for temporary modifications, site-specific standards and assessment locations.
*Lead(acute) = See 36.6(4) for temporary modifications, site-specific standards and assessment locations.
*Lead(chronic) = See 36.6(4) for temporary modifications, site-specific standards and assessment locations.
*Manganese(acute) = See 36.6(4) for site-specific standards and assessment locations.
*Manganese(chronic) = See 36.6(4) for site-specific standards and assessment locations.
*Silver(acute) = See 36.6(4) for temporary modifications, site-specific standards and assessment locations.
*Zinc(acute) = See 36.6(4) for temporary modifications, site-specific standards and assessment locations.
*Zinc(chronic) = See 36.6(4) for temporary modifications, site-specific standards and assessment locations.
*TempMod: Ammonia = Willow below Creede WWTF.
*TempMod: Cadmium = See 36.6(4) for temporary modifications and assessment locations.
*TempMod: Copper = See 36.6(4) for temporary modifications and assessment locations.
*TempMod: Lead = See 36.6(4) for temporary modifications and assessment locations.
*TempMod: Silver = See 36.6(4) for temporary modifications and assessment locations.
*TempMod: Zinc = See 36.6(4) for temporary modifications and assessment locations.
/ Physical and Biological
DM
/ MWAT
Temperature °C
/ CS-II
/ CS-II
acute
/ chronic
D.O. (mg/L)
/ ---
/ 6.0
D.O. (spawning)
/ ---
/ 7.0
pH
/ 6.5 - 9.0
/ ---
chlorophyll a (mg/m2)
/ ---
/ 150*
E. Coli (per 100 mL)
/ ---
/ 126
Inorganic (mg/L)
acute
/ chronic
Ammonia
/ TVS
/ TVS
Boron
/ ---
/
/ 0.75
Chloride
/ ---
/
/ ---
/
Chlorine
/ ---
/
/ 0.011
Cyanide
/ 0.005
/ ---
/
Nitrate
/ 100
/ ---
/
Nitrite
/ ---
/
/ 10
Phosphorus
/ ---
/
/ 0.11*
Sulfate
/ ---
/
/ ---
/
Sulfide
/ ---
/
/ 0.002
/ Metals (ug/L)
acute
/ chronic
Aluminum
/ ---
/ ---
Arsenic
/ 340
/ 100(T)
Beryllium
/ ---
/ ---
Cadmium
/ varies*
/ varies*
Chromium III
/ TVS
/ TVS
Chromium III
/ ---
/ 100(T)
Chromium VI
/ TVS
/ TVS
Copper
/ varies*
/ varies*
Iron
/ ---
/ 1000(T)
Lead
/ varies*
/ varies*
Manganese
/ varies*
/ varies*
Mercury
/ ---
/ 0.01(T)
Molybdenum
/ ---
/ 160(T)
Nickel
/ TVS
/ TVS
Selenium
/ TVS
/ TVS
Silver
/ varies*
/ TVS
Uranium
/ ---
/ ---
Zinc
/ varies*
/ varies*

2

REGULATION #36 STREAM CLASSIFICATIONS and WATER QUALITY STANDARDS

Closed Basin-San Luis Valley River Basin

3. All tributaries to the Closed Basin excluding the listings in segments 2a, 2b, 2c, and 4 through 13.
CORGCB03
Designation
Reviewable
/ Classifications
Agriculture
Aq Life Warm 1
Recreation E
Water Supply
Qualifiers:
Other:
Temporary Modification(s):
Arsenic(chronic) = hybrid
Expiration Date of 12/31/2021
*chlorophyll a (mg/m2)(chronic) = applies only above the facilities listed at 36.5(4).
*Phosphorus(chronic) = applies only above the facilities listed at 36.5(4).
/ Physical and Biological
DM
/ MWAT
Temperature °C
/ WS-II
/ WS-II
acute
/ chronic
D.O. (mg/L)
/ ---
/ 5.0
pH
/ 6.5 - 9.0
/ ---
chlorophyll a (mg/m2)
/ ---
/ 150*
E. Coli (per 100 mL)
/ ---
/ 126
Inorganic (mg/L)
acute
/ chronic
Ammonia
/ TVS
/ TVS
Boron
/ ---
/
/ 0.75
Chloride
/ ---
/
/ 250
Chlorine
/ 0.019
/ 0.011
Cyanide
/ 0.005
/ ---
/
Nitrate
/ 10
/ ---
/
Nitrite
/ ---
/
/ 0.05
Phosphorus
/ ---
/
/ 0.17*
Sulfate
/ ---
/
/ WS
Sulfide
/ ---
/
/ 0.002
/ Metals (ug/L)
acute
/ chronic
Aluminum
/ ---
/ ---
Arsenic
/ 340
/ 0.02(T)
Beryllium
/ ---
/ ---
Cadmium
/ TVS
/ TVS
Chromium III
/ 50(T)
/ TVS
Chromium VI
/ TVS
/ TVS
Copper
/ TVS
/ TVS
Iron
/ ---
/ WS
Iron
/ ---
/ 1000(T)
Lead
/ TVS
/ TVS
Manganese
/ TVS
/ TVS
Manganese
/ ---
/ WS
Mercury
/ ---
/ 0.01(t)
Molybdenum
/ ---
/ 160(T)
Nickel
/ TVS
/ TVS
Selenium
/ TVS
/ TVS
Silver
/ TVS
/ TVS
Uranium
/ ---
/ ---
Zinc
/ TVS
/ TVS

2